NASA manned Mars mission details emerge

A 400,000kg (880,000lb) Marship would be assembled in orbit using the Ares V cargo launch vehicle for a 900-day mission to the red planet, according to details that have emerged about NASA's new Constellation programme's manned Mars mission.

The spacecraft would take a "minimal crew" to Mars in six to seven months, with the crew spending up to 550 days on the surface, according to the programme's design reference architecture 5.0, currently in development.

Each of the three to four Ares V rockets used to launch the Marship elements into low Earth orbit would need a 125,000kg payload capacity and use a 10m (32.7ft) fairing.

Crews would be sent every 26 months, will need up to 50,000kg of cargo, use an aerodynamic and powered descent method and the 40min communications delay between Earth and Mars would require autonomy or at least asynchronous operation with mission control.

Notionally launched in February 2031, the first crew's flight would be preceded by the cargo lander and surface habitat being sent in December 2028 and January 2029, respectively using two Ares V launches.

The lander will arrive around October 2029 and the habitat November the same year. Nuclear power is the preferred surface energy source. The crew will arrive in August 2031.

A second mission's habitat and lander will be launched by two Ares Vs in late 2030/early 2031 to reach Mars at the same time as the first crew. In the first quarter of 2033, the second mission's crew will leave Earth to arrive at Mars by December, while the first crew leaves Mars in January 2033 after a 17-month stay, to reach Earth by September.

It also states, "Conjunction class missions (long-stay) [have] fast inter-planetary transits. Successive missions provide functional overlap of mission assets," referring to the presence of a following mission's habitat and cargo lander being on Mars when its preceding mission's crew are there already.